Codeforces 刷题记录（其二）：rating 2200
总结
为了提高训练效果，将 AC 的时限缩短到了一小时。
这也导致我耗费了一个半月，做了七八十道题，才终于通过了 2200 rating 的难度。
感觉这个训练方法相当有效，经过这两个多月的练习后，可以说我现在的水平（至少是打 cf 比赛的水平）甚至已经超越了之前在校队的时候，果然是勤能补拙啊。。。
七月下旬就要开始做 2300 rating 了，加油加油。
2025 年 6 月
https://codeforces.com/problemset/problem/1998/E1 - AC, 用时一个半小时，好题
https://codeforces.com/problemset/problem/1997/E - AC,用时一个半小时
https://codeforces.com/problemset/problem/1993/D - AC
https://codeforces.com/problemset/problem/1991/F - 未做出, 写了200行结果样例都过不了…
https://codeforces.com/problemset/problem/1967/B2 - AC, 用时一个半小时
https://codeforces.com/problemset/problem/1954/E - AC
https://codeforces.com/problemset/problem/1909/F1 - 未做出, 花了一小时想了个结论发现过不了样例,最后放弃. 题解的做法很有启发性, 好题, 值得收藏
https://codeforces.com/problemset/problem/1901/E - AC,犯了个很愚蠢的小错误,调了很久,总共耗时两小时
https://codeforces.com/problemset/problem/1898/E - 未做出,其实是简单题
https://codeforces.com/problemset/problem/1867/E2 - AC,用时两小时
https://codeforces.com/problemset/problem/1860/D - AC
https://codeforces.com/problemset/problem/1858/D - AC, 用时1h10min
https://codeforces.com/problemset/problem/1854/B - 未做出,思路完全正确,尝试实现了很久但是没写出来,最后看答案才意识到用 bitset即可…退役久了连这些东西都忘记了…
https://codeforces.com/problemset/problem/1848/D - AC
https://codeforces.com/problemset/problem/1837/E - AC
https://codeforces.com/problemset/problem/1832/E - 未做出,其实是简单题,不要看到组合数就害怕…
https://codeforces.com/problemset/problem/1815/C - WA on 2. 因为读错题导致加成了双向边
https://codeforces.com/problemset/problem/1808/E1 - AC
https://codeforces.com/problemset/problem/1806/E - TLE on 10, 好题
https://codeforces.com/problemset/problem/1795/E - AC
https://codeforces.com/problemset/problem/1788/E - AC, 做了2h30min,前两个小时读错题了写了很久,其实是简单题
https://codeforces.com/problemset/problem/1777/E - AC
https://codeforces.com/problemset/problem/1763/E - AC
https://codeforces.com/problemset/problem/1763/D - AC, 但是借助了官方数据debug,且花费两小时.做法其实很好想,但是实现的时候需要清晰的思路
https://codeforces.com/problemset/problem/1737/D - 未做出,思路正确,但是想多了导致搞错时间复杂度, 好题
https://codeforces.com/problemset/problem/1736/D - 未做出,智力题,可惜没有智力…好题
https://codeforces.com/problemset/problem/1717/E - AC, 用时1h30min
https://codeforces.com/problemset/problem/1704/E - AC
https://codeforces.com/problemset/problem/1695/D1 - WA on 5,好题
https://codeforces.com/problemset/problem/1672/E - 未做出,好题
https://codeforces.com/problemset/problem/1657/E - TLE on 6, 下次遇到这种计数题最好意识到可以前缀和优化
https://codeforces.com/problemset/problem/1656/E - AC
https://codeforces.com/problemset/problem/1646/E - AC
https://codeforces.com/problemset/problem/1641/C - 未做出, 好题
https://codeforces.com/problemset/problem/1635/E - AC
https://codeforces.com/problemset/problem/1627/E - AC, 用时1h20min
https://codeforces.com/problemset/problem/1622/E - AC, 用时1h30min
https://codeforces.com/problemset/problem/1616/E - AC, 用时1h20min,且使用了官方数据debug
https://codeforces.com/problemset/problem/1615/D - 未做出,好题
https://codeforces.com/problemset/problem/1583/E - AC,用时1h20min
https://codeforces.com/problemset/problem/1580/C - AC, 用时1h20min
https://codeforces.com/problemset/problem/1567/E - AC
https://codeforces.com/problemset/problem/1559/E - TLE on 9, 理论复杂度是对的,但是因为常数大T了,后面改了一下写法, 把二维数组换成两个一维来回倒腾就过了, 卡常是坏文明…
https://codeforces.com/problemset/problem/1557/D - 交到测评机上报RE了,可是本地跑没报错, 输出了正确答案, 一直没找到问题出在哪, 改了一下写法, 规避了用到指针的地方, 但是又在 24 个点MLE…
https://codeforces.com/problemset/problem/1556/E - AC
https://codeforces.com/problemset/problem/1552/F - AC
https://codeforces.com/problemset/problem/1543/D2 - AC
https://codeforces.com/problemset/problem/1542/D - AC, 用时1h20min
https://codeforces.com/problemset/problem/1537/F - AC
https://codeforces.com/problemset/problem/1537/E2 - WA on 16
https://codeforces.com/problemset/problem/1535/E - AC
2025 年 7 月
https://codeforces.com/problemset/problem/1503/C - 一个小时内没写完, 大致搞了一个单调栈 + 线段树, 看了正解之后才发现解法十分简洁, 好题
https://codeforces.com/problemset/problem/1500/B - AC, 用时1h50min
https://codeforces.com/problemset/problem/1498/E - AC, 用时2h. 其实是简单题, 但是在最开始的一个半小时读错了题面, 尝试看题解时才发现
https://codeforces.com/problemset/problem/1477/C - AC
https://codeforces.com/problemset/problem/1474/D - WA on 2. 好题, 看似简单但是很难写对, 出题人在题解中给出的写法很优雅
https://codeforces.com/problemset/problem/1470/D - AC
https://codeforces.com/problemset/problem/1467/D - AC
https://codeforces.com/problemset/problem/1461/E - WA on 83. 写了很久, 一直没找到很简洁的写法, 但是如果仔细思考, 发现分类讨论即可.
https://codeforces.com/problemset/problem/1438/D - AC, 用时 1h10min
https://codeforces.com/problemset/problem/1428/E - AC
https://codeforces.com/problemset/problem/1407/D - AC
https://codeforces.com/problemset/problem/1406/D - AC
https://codeforces.com/problemset/problem/1400/E - WA on 4, dp 状态很好想, 但是转移的时候写错了, 漏掉了一个情况
https://codeforces.com/problemset/problem/1398/E - RE on 2, 检查发现是对一个倒序排序的set进行lowerbound查询, 但是却忘记它是倒序的了, 访问了不符预期的值… 改正之后遂通过
https://codeforces.com/problemset/problem/1389/E - AC
https://codeforces.com/problemset/problem/1373/E - AC
https://codeforces.com/problemset/problem/1338/C - AC, 用时1h20min, 好题
https://codeforces.com/problemset/problem/1336/C - 未做出, 十分有趣的dp, 好题.
https://codeforces.com/problemset/problem/1334/E - 未做出, 做法其实很简单, 但是没有意识到 x, y 都是 D 的因子, 算错复杂度了
https://codeforces.com/problemset/problem/1333/F - AC
https://codeforces.com/problemset/problem/1327/D - AC, 好题
